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Published on: December 14, 2017
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Evidence against solar influence on nuclear decay constants
1European Commission, Joint Research Centre (JRC), Retieseweg 111, B-2440Geel, Belgium.
Physics Letters. [Part B]
|January 7, 2017
Summary
This study disproved the hypothesis that the Sun
Area of Science:
- Nuclear Physics
- Astrophysics
- Metrology
Background:
- The hypothesis proposed that variations in Earth's proximity to the Sun could influence nuclear decay rates.
- Such variations, if present, could impact precise measurements in nuclear science and dating techniques.
Purpose of the Study:
- To experimentally test and disprove the hypothesis of Sun-proximity-induced variations in decay constants.
- To establish precise upper limits for any potential annual oscillations in nuclear decay rates.
Main Methods:
- Activity measurements of mono-radionuclide sources were conducted over extended periods (up to 40 years) at 14 international laboratories.
- Analysis focused on residuals from exponential decay curves to detect annual oscillations and systematic deviations.
- Instrumental and environmental factors were carefully considered to distinguish true decay variations from measurement artifacts.
Main Results:
- No statistically significant annual oscillations in decay rates correlated with Earth's orbital distance were observed.
- Systematic deviations were attributed to experimental conditions, not solar proximity.
- Upper limits for the amplitude of annual oscillations were set between 0.0006% and 0.008%.
Conclusions:
- The hypothesis of Sun-proximity-induced decay constant variations at the permille level is disproved.
- No natural impediments to achieving sub-permille accuracy in half-life determinations were found.
- This validates the reliability of nuclear dating, SI unit establishment (becquerel), and international activity standards.
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